Tyre Volume - Which Is Fastest For XC?
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- เผยแพร่เมื่อ 20 ต.ค. 2016
- Traditionally Cross Country racers opted for narrow tyres in the belief that it would reduce rolling resistance. Times have now changed with riders opting for wider tyre, so with that in mind we sent our resident XC whippet Joe Norledge out to test which is faster.
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This is one of the best efforts to control variables I have seen for this type of video. Well done. I was glad you set the tires to an appropriate pressure for their size, but wouldn't have thought of using Laplace's law!
Test rim width next! 2.35 tires on 21mm, 24mm, 27mm, and 30mm internal width rims(Easton has 24, 27, 30 internal on their arch line). Decreasing pressure as you increase width to maintain tension(modifying your equation to T=P*((Tire Casing Width+Internal Rim Width)/3.14) )
Hi Ian. Thanks for the mentioned equation. We verified the calculation in an experiment with different rim widths and it works. However, I can't see the mathematical logic behind. Could you give me a hint?
Beat Müller I have a carbon rims with 23mm internal rim, I have serius problems in loose terrain because I’m really “blockish”, 2.35 (rekon, ardent, etc...) in the front will be ok?, or is it too narrow for 2:35??
Thanks
@@alejandrog.c1939 good enough, mayby my comment will help someone. 25mm internal works perfectly for 2,35 Maxxis, 23mm internal should too, aspecially because Maxxis tires are a bit undersized.
I'm impressed, you guys have come a long way from your first experiments on the channel!
You prefaced the experiment saying that you don't expect your results to be scientific, but I'd say you got some good data. The number of trials you did and the tests you used seemed sufficient. Keep it up!
Thanks!
Nice Experiment, your conclusions makes sense to me.
This has been my experience.
Always used 2.2 X-King but recently tried 2.4 on the front, felted more rolling resistance because of the bigger knobs, but the grip is outstanding.
Last year used 2.35 Ikon on the front and the good thing about this specific tire is that is the same size knobs but spreaded on a wider tire = same rolling resistance as 2.2 with better grip.
I just ordered Vittoria Mezcal 2.25 because now I'm running Aspen 2.1 and they have very low grip and are really narrow compared with 2.2 Ardent Race on the front (good grip and fast but heavy tire).
Thanks for the quality of your content
Keep up these types of tests. Thanks!
Different Rim widths would be amazing tests, Old standard of 19mm internal width with a 2.0 tire, and a 2.35 or 2.5 with a 24mm internal width, then you can also include the standard 2.2 tire with a 21mm rim
always enjoy these analysis videos! keep them up, you're one of the few cycling channels that provide information this accurate matched with high production value
Thanks. Good to know the hard work is appreciated!
Hey XC rider! I've been used different tyre from early from 1.90/ 95 till now I'm used 2.20 & 2.25 (on different mtb).
They are superb and feel the different (track) tyre size from 1.9 till recent 2.2! As I can said for all rounder trail!
Greetings from XC rider Kuala Lumpur.
I absolutely love my set of Ikon 2.35"s
The Ikon 2.35 is such a versatile tire that rolls fast and provides enough grip for a ton of riding scenarios. Thanks for the test video!
Which is better, Ikon or regular Ardents?
@@CowneloAlvaroid Ardent has a better rolling, which is suitable for rear wheel and ikon on the front for better grip and controlling. I know it's a 2 year old comment, still this would be helpful to others.
It will help me to buy my first tyres after my currently stock 2.0 will wear off. Thanks for useful info, guys! Great job!
No worries, thanks for watching!
Awesome video, exceptional data. Thanks guys.
Glad you enjoyed it!
Interesting results. I'm riding 2.25 wide at the moment and I have found it to be a good sweet spot for my riding.
Maxxis aspen 2.25 front and rear FTW
@@Fred_the_1996 Sounds terrifying haha. Aspens in my area are a death sentence
Thank you very much. Very good article. Very scientific. Just what I was looking for.
Briliant!
This is how test should look like.
Cheers.
Thanks for watching and glad you enjoyed it!
One possible point to doing experiments is to go outside of what is "normal", i.e. include tire sizes that XC racers aren't even looking at, like 2.6 or even +3.0. Because with 2 data points, (2.0 and 2.35) you're always going to have a straight line. Would multiple widths show a trend from narrow to wide, or would there indeed be a sweet spot. I know it would be a lot of work, but it would also be a lot of downhill runs, so fun.
Great test. We should see more of these real world tests in the ever changing industry standards.
Now do the same thing as a group comparison between the top 10 brands at 2.25 size. This would be a massive undertaking, but super useful to anyone racing XC. Fantastic video, more of this and more real science. It's 2016, real data over individual opinions is vital.
This video is great, please do the updated test so we can see if anything is different
Thanks for watching! What would you like to see tested next?
They were heavy but I loved the set of Panaracer Fire FR's I had on an old bike. At 2.4" wide and a tread like a motocross tire they could go anywhere, if they were lighter they would have been my perfect tire.
Bummer you didn't test the 2.2 Ikon vs the 2.35 but in any case, GREAT test. :)
For the XC lap, best to compare the product of time and power instead, average energy output. It would be better to average the instantaneous energy outputs, but roughly the 2.0 required 179 kJ vs 182 kJ on the 2.3. Makes sense since the 2.3 is heavier. Playing number games, if you applied the same amount of power to the 2.0 as the 2.3, you would have finished the lap faster with 9:14.45
Despite you say this is not science, the procedure was much more scientific than almost anything I've seen in this sort of videos. Thumbs up!
Great job on this guys. Fat=smooth, smooth=fast, Fast=fun
But more data! Those last two tests a comparison don't make. Need more data points.
There is a cut-off or sweet spot. If it is too fat 3.0" for example, it becomes too slow. Need a sweet spot 2.35"?
Would be interesting a 5/5 rolling 3/5 grip tires with soft compound vs a wider 3/5 rolling 5/5 grip medium compound tires. What do you think is faster, in general?
What internal rim width was this test done with? I am wondering if the 2.35 IKON is too wide for my 19mm internal width rim. BTW, ON PAPER if equal wattages would have been layed down I believe the lap time would have been 9:42 on the wider tires. 8 seconds slower than the narrower tire.
I think a lot depends upon the terrain. Wide tyres are good for the sort of woodland and tracks that you showed in the video, but for climbing on grass, for example, fatter tyres can slow you down. Am am lucky in that I have winter and summer bikes. The summer machine has 2.1 tyres fitted, with slightly lower pressure. This is because the ground tends to be a bit dryer in the summer and a bit more solid. So a bit of tyre suspension will give a plusher ride. However, in the winter I want a tyre that will cut through the clag, not getting clogged up, but also able to get to the grippy stuff under the mud, rather than floating over the mud. So in winter I run with 1.8 Panaracers. The Fire XC pro also has the benefit of being able to get on and off the rim quite easily, which is handy when you are in the middle of nowhere.
So, in Summer I run with 2.1 s with small profile nobblies. A summer tyre. In winter I run with more pressure, but skinnies.
Works for me.
Luck
I accidentally ordered 2.125" tires for my 20" GT bmx which I used off and on road. Putting the heavy tires on, the bike was so noisy, like an F250 on TSL Boggers. It was SO SLOW. I had to pedal my legs out to keep up with my friends. I replaced them with 1.50" and got fast. BMX track (hardpacked dirt and little gravel) performance was great. Riding my aluminum GT 24" bmx around the city, switching from 1.75" tires down to 1.50" tires increased speed, acceleration, reduced rider fatigue.
I run 2.25 back and 2.4 front. Very good combo
I would be interesting with a mud test to see how the wider tires performs. Also a XC rim width test would be interesting.
Great video. I was debating between 2.1/2.25 vs 2.35 for Oramm that has almost 11000' of climbing that has some pretty fast and aggressive downhill in 60 miles. This helped solidify my decision to stick with the wider tires Im used to and prefer...
Normalized vs Average Watts. I believe that you should have used average Watts rather than normalized power. Normalized power is analogous to Root Mean Square (RMS), but to the 4th power, then using the 4th root, rather than the second as the RMS. This is done to get an estimate of impact on the body of the Wattage variation or spikiness - physiological impact. This does is not directly the power input that propels the bike, which is what you actually wanted to measure here. That said, there average Watts is also only an estimate to the bike power input in the two comparisons, because it does also depend on under what conditions those Watts were used. For example, you could get the same average Watts in two comparisons, but different outcomes due to variation of application or distribution of the Watts across the rides. It would be very difficult to have meaning of a second and half difference with all these other estimated variables. What I could get out of the experiment is that they appear to perform similarly on time. So then get what otherwise suits you best, comfort, feel, availability, etc.
please make the same test with some 3.0 inch tires included
I like to consider myself a mix between XC and trail riding on a hard tail and wanted to find the right size between 2.1-2.4 for me!
By having a lower pressure in the wider tire, there's actually a larger contact patch. I'm not sure how that plays out in terms of rolling resistance. I'm curious how Bontrager came up with that equation. I've never heard of it before. Physics! Hey I don't feel so pissed off about my pristine trails being shredded by loggers. It looks like we've all got forest issues.
Or did you maybe output more watts on the second test because the wider tires allowed you to feel like you could actually get the power down? I would say probably the case, especially give how wet it looks. Wider tires FTW! Nice vid!
I love vids about tires, thx
This is all okay on a trail centre course that has a load of hardcore stone covered fire roads and trails, but come up to the Lake District and ride some natural trails with a load of muddy slop, and you will find that a slim tyre will sink through the mud faster and get to the hard grippy stuff. I used to race xc and had a range of tyres and changed them depending on the track and conditions on the day.
I think rear suspension plays into this also. I suspect the fastest tire size is the lowest volume that reduces general trail chatter to negligible levels, which should be thinner on full sus.
The wider tire was still faster on the last test despite the difference in watts, you would have required 328W on the 2.0 to match the time of the 2.35 tire.
Is it because 2.35 tires have larger diameter than 2.0? Meaning less angle of attack on 2.35 than 2.0?
my old xc came with 2.0 and I haven't ridden it in years. the I guess the max is a 2.4 so thinking about doing those or 2.35 because it still has the factory tires on it. hopefully I will start riding it again.
I run 2.2 for my XC bike and dirtjumper because they feel perfect for crosscountry, dirtjumps and street.
did you prefer the feel or comfort of the bigger tires as well? as a secondary aspect of riding, perhaps more important for marathon type races?
Great test! Glad GMBN didn't test this. They would change the bike, tire tread, and rider when comparing wider vs narrower.
Mmmmmm don't think they would.... They're not idiots.....
+Will Menday they will, they do it everytime
I like their videos but their tests are just stupid :D
@@hobbesthetiger7468 their tests are not tests most of the time, they are just advertisements pretty much, and they are repeating themselves over and over now, I stopped watching about a year or so ago. I think the issue with this channel is that they are still sticking to that shitload of videos per week formula which is not needed anymore as the channel is big enough, and they are struggling to put out quality/original content.
Back when I used to actively ride MTB (26ers),I had a preference for wide front tyres & narrow rears...Usually a 2.1 front with a 1.95 rear...And usually a blocky,directional type tread on the rear with a knobbly unidirectional tread on the front...
Dia buat perbandingan masa, keberkesanan, dan wattage.. pada pelbagai permukaan jalan.. antara sepasang 2.0 dgn sepasang 2.3.. ksimpulannya 2.3 lbh efektif dan cepat pd pelbagai permukaan jalan brbanding 2.0.. tp dr segi wattage, 2.3 effort dia lbh byk dr 2.0..
Dr segi sedap, rasanya depan 2.1dgn belakang 1.95 mmg sedap tp tidak pada semua permukaan.. ikut pngalaman sy bila masuk seksyen jalan yg agak loose mcm batu2 loose @ pasir2 loose yg libatkan climbing dan descend.. 1.95 samada belakang shj @ dua² pakai 1.95 mmg x sedap.. agak payah nk kontrol.. climbing akan spin sikit2.. berbanding dgn tayar 2.1 ke atas.. sy pernah cuba kedua2 depan belakang sama saiz 1.95 dan 2.1 & combo belakang 1.95 n 2.1 depan.. 2.1 lbh efisien.. sekadar berkongsi
I have a 25mm inner rim with, on my Trek XC bike, and I am running 2,25 Rocket Ron tyres. I feels SO damm nice :-)
I dig the RoRo's too. But they do not hold up in sharp rocky conditions. I tore off a number of side nobs and had to bin the tires. Great tires though for the right terrain. (hardpack to loose) but not loose rocks or sharp bedrock.
Very helpful.
In our country, our course here has a mixture of road and off-road. I think 2.1 is better. I’ve tried the 2.3 and they are so hard to spin in the rear and very heavy.
Just a suggestion, get a really good, stable E-BIKE and then simply put it on max speed of xx and go for 500m without any jumps or stuff like that on a possibly flat terrain with simple line to follow and then measure the speed =)
I find your suggestion pretty worthy, but that would do good for a road bike or a road-race scenario. It wouldn't shed any conclusions on Enduro/All mountain tracks. Plus on enduro, e-bikes wouldn't give you much analysis in terms of power that we throw in.
Dhananjay Bhardwaj Well they said the tyres are made for less rolling resistance and not softening the bumps, jumps, rocks, etc. So you should know which tyre is faster, after all most of the track is flat anyways and maybe I said it in the wrong way i didnt meant road flat i meant small rocks, small roots and stuff like that where the tyre is gonna be most of the time and where you can follow a straight line but yeah then it comes to grips in corners and that chagnes stuff, true
Tony Eatinsky Totally agreed :)
Tony Eatinsky - I scrolled down to the comments to say make this suggestion, thinking I'm gonna have a really witty smart comment...oh well, haha, glad we're both thinking on a similar wave length. I hope they try this test too.
The roll down test is more consistent.
so guys looks like xc hardtails Start to become rowdy with wider tyres and dropper posts
Hey man I’m from 2021.
Congratulations you predicted the future!
Ultimately the tire style should make more difference. I have Xcaliber 8. 3rd one since 2008. Small Block 8 was my favourite rear tire before. There appears to be a better version the Kozmik lite II. I see no reason to change the front XR2 but 2.2" happens to be available. My old Small Block 8 was a 2.1"
You need to compare a long fast sweeping descent on hardpack.
Good video
What about rim width, i just changed the stock wheels on my Scott 735 to a set on DT Swiss 1501 22.5 mm and 2.25 Racing Ralph up from 17 mm 2.1 Rocket Ron
Ride definitely smoother on a hardtail but can't say faster on the hills possibly in part due to about 800g in weight. Hope to hear from you and keep those hardtail vids coming.
Try playing tire pressure. 25 psi front and 27psi back is a good starting point. up 2psi and down 2psi.
This ia great way more scientific than other channels tests (gmbn)
Great job:)
Not sure about using that tension formula. As the tire deforms under weight, there is an area contact patch. It's not being supported by a single line across the tire. I suggest squaring the tire width.
Do you have already an test of 2.25 vs 2.35 »?
+1 for Thomas McNeice - Neon Lights (instrumental) music in the beginning of the video.
Have you guys heard of NOX carbon wheels located in Tennessee? Any feedback on them because I got an amazing deal on a 2016 Focus Raven MAX-SL with XTR and just going to upgrade the DT 1700 wheels
thank you!
How about this test with a full suspension xc bike?
so what about comfort and road feel/feedback? Should have better feel of whats going on w the surface w the 2.0
Please do this test with an OPEN 1+ 29 X 2.35 vs 27.5 X 2.8 tires
how about using a wider in the back and a narrow in the front, will it have better handling?
hi great video thanks . could I ask you what tyre pressure you would use on maxxis high roller 2 tyre size 29 / 2.30 thanks
Maybe another test is a wider rim with the 2.35 width tire. I would be interested in the results.
Great idea but I was hoping to see a 2.2 or 2.3 tire up against a plus tire, 3.0. I would love to see a test like that.
Stfu no one uses 3.0 on xc
Stfu no one uses 3.0 on xc
@@hulktruck3264 I can read, didn't need to send it twice. Also, that comment was 2 years ago. Also, STFU? Really, you are that upset about a comment on TH-cam? Wow...you need more in your life.
@@johngraham6506 Stfu no one uses 3.0 on xc
Wouldn't the wider tyres, with less pressure, give far better grip when breaking? Meaning you can go faster for longer before braking?
The ChaosEngine that would be a motorbike on a tarmac circuit
@@enricolionello9044 Nope. The area of the contact surface actually makes less diference on tarmac versus lose soil.
On smooth surfaces the friction force depends on the coeficent of friction between the materials and the force perpendicular to the plain, not so much on the area of contact, but on lose soil, since there is very little friction between the materials, the friction depends more on how the tire digs in, and thus on the area of contact, since a larger area means more knobs digging in on the dirt.
Just think of ice as an extreme example. The friction between rubber and ice is very low, so the tires have metal spikes to dig into the ice. Meanwhile F1 cars and GP bikes have a plain tires.
do you recommend running the same tires size front and rear? 2.3 front and rear or running 2.0 rear 2.3 front? why would you need to run a thiner tire in the rear? thanks
The general wisdom is to have grippier front than the rear. And that's it. Not everyone may agree with me, but I think that having the same front and rear just doesn't make sense. At the peak of the performance demand, namely downhill, manufacturers sometimes design different tread patterns for the front and the rear. That's because both wheels do different jobs.
The idea is that while the rear can slide about and you just keep on riding, once you lose the front, you go down.
Another thing is that at least 60% of your weight sits on the rear tire and that's where most of the rolling resistance comes from. So if you have the same tires at the same pressures, the rear will deform/comply with the terrain and therefore have more grip than the front simply by having more weight on it.
And the last thing, what you have on the front adds very little to the real-world rolling resistance, especially when climbing.
In conclusion:
Front should be gripper and have less pressure. Higher rolling resistance makes very little difference.
Rear should have more pressure, faster tread and less rolling resistance.
Tire width is very individual thing. Some 2.4 tires are physically thinner than some 2.25 ones. But I think that most people will tell you to have a wider tire on the front simply because it seems as common sense that the wider tire has more grip. I say worry about tread and rubber above all things.
The science is perfect
which one front and back? im planning to put up also.crossmark II 29.2.25 front and aspen 29.2.1 back. any thoughts? thank you.
Would it be too much to have for XC style, a carbon wheel set (Newmen 1100 gr..) + Minion DHF + DHR II 2.3"? I cannot decide between those 2 tyres and Schwalbe Racing Ralf + Ray 2.25".. Any help on this?
3 minutes in and I am getting nerdgasms. Tickles me in all the right places.
Are all the tires that you are testing with the same TPI? Do you know if there is much of a difference between Ikon with 60TPI vs Ikon with 120TPI? I found some ikons very cheap but they are 60 TPI. I know that TPI influences resistance but the question is, how big is the influence?
Joe Norledge , do you know if it TPI makes a real difference?
Hey guys... What about on tarmac? & what about mixed - Wide front\Thin rear - tyres? O.O
Several people I know run 2,0 in the rear and 2,2 up front (XC).
What about All Mountain & Enduro? Thanks...
I run 2.25 rear 2.35 front on velocity P35 rims, bike just rolls over everything
My plan is a 2.4f\2.2r on 25mm internal width - I hope they are adequate... =]
This tire is beautiful
Narrow tires ar often used by xc racers because they can be firmer because of the air volume. For example a 2.1 tire can be pumped up more.
compare the Ikons with the Ardent Races
I ride 60% on pavement/tarmac and 40% off-road/. Is the 2.4 Maxxis Holy Rollers great for my riding style?
I have serius problems in all the descents (small equilibrium problems), which do you prefer on the front for stability ?, ikon 2.35, Ardent 2.25, Ardent Race 2.35, Rekon 2.25 or Xking 2.4??, this is for loose terrain (deep gravel ) long descents with 8/10% inclination and curves. But I need good rolling resistance for climb. Thanks a lot Ed: Carbon Rims, 23mm internal wide"
Hi Alex, what did you choose and how did it goes? I love to hear from you. I am in the middle to figure out. I am same thoughts at starting point and now I am considering Forekaster 2.35 front (735g) decent rolling speed, and Aspen 2.25 rear (650g) fast rolling speed. This is a super light weight and it should feel lively on the trail. But - I have not tried it yet. I want to hear what you tried.
Which tire were you using when you scraped up your left elbow?
Joe had a very silly slow speed crash when a kerb jumped out in front of him on his road bike. First one in years, apparently!
I have 26x2.1 and 26x2.3 tires. Should I put the larger one in the front or back?
for the last test : just make a time (in seconds for instance) / watts ratio. the lower ratio should give you the fastest tyre
Fat tire lap was 98.4% of the skinny tire lap, faster by 1.6%. Power required for the faster lap was 3.5% greater than the slower lap. Based on this the fatter tires were less efficient.
A ratio of time to watts is not valid because time and power are inversely related. Consider if the times had been identical: by your logic the win would go to the higher wattage, which doesn't make sense.
What do you think of 2.35 tires on 19c rims? Is it stable, or I better stick to the 2.25 tires?
I think 2.25" tires is your max for 19mm rim. It is probably very light and fun.
What's the rim width use in both tires and all of the tires? don't you think we deserve to know?
To clear out the little doubt, you could just go back and try another round, this time trying to get the normalized power closer to each other
The added weight of larger tires and wheels is negligible when compared to the benefits of reduced rolling resistance and increased grip.
And the proof is really simple, just think about what wheel sizes are being raced at world cups nowadays, versus what was being raced ten years ago.
Larger wheels do require more energy to get up to speed, but the major difference comes from the increased mass itself and not the fact that it is rotating.
2.25 was standard for XC, already 10 years ago.
I use the icon 2.6 and it’s great except for hard braking but you get used to sliding
Skinnier tires will be faster in really muddy terrain but thats about it. Wider tires grip better, absorb shock better. Being more comfortable and not beaten to death(especially on a hardtail) saves energy and makes a huge difference on a long ride. Skinnier XC tires in my shop dont sell anymore. Even roadies have gone wider!!!
please do tests with a plus bike, something around 3 inches?
i thought the same, a 29er vs a + in the same frame, thats' what people actually want to know, not if a slightly wider tyre is better, they can do that themselves with minimal outlay compared to a new wheelset & tyres.
Hi James, you're in luck as we've done just that - 29er vs 650B+ (this was the test Seb did that Joe name dropped at the start) th-cam.com/video/w6TMA2vI8bA/w-d-xo.html
what about 29+. thinking about buying a trek stache 7 29+ and I want to know how agile it feels in comparison to smaller/thinner wheels. thanks for any reponses BikeRadar
We've had a look at the Stache 9 before but we're certainly keen to explore some more tyre tests th-cam.com/video/7hj0JWqo0kE/w-d-xo.html
BikeRadar thanks. would you say that the review and your thoughts of the stache 9 applies to the stache 7 as well?
2.0 or 2.10 in the back, 2.20 on the front... Im currently running a 2.10 small block in the back and a 2.10 Crossmark II in the front
if i wanted to mount maxxis aspen wt 2,4 + rekon race wt 2,4, which one is better at the rear / front? thank you
Does this apply to gravel bikes as well?
surprises me!
peace guys, guys
which 700c wheelset that rim specific brake but can allow up to 2.0 tyre?
Help me I am 14 years old so I will still grow I will be building a bike (a non cheap high end xc bike build) so I wanna make it count because I don’t wanna spend more money switching from 27.5 to 29 once I grow (frame, fork, wheelset and etc) so even If i am small will you tolerate mo to go 29? I actually tested a 29er and kinda liked it it’s not that heavy for climbs like they tell me but problem is steering is kinda more controlling me not me controlling the bike should I get 29 or 27.5 because every xc bike I see is 29
does anyone know the title of the song in the background?
how do I find the correct pressure? looks like I'm still running my tyres too hard.
Experiment. Carry a pump and a pressure gauge with you and adjust on the fly. I'm running tubeless 2.2's, weigh 140lbs and have gone down to 18psi which is probably the absolute low end and probably right around 20psi will be my sweet spot. Depending on how much you weigh, if you're running tubeless, what width (wider = lower psi) and what kind of ride you prefer will dictate your preferred psi.
This seems to contradict other tests floating around youtube that come at it from a "gravel bike versus hardtail" angle. In that realm the gravel bikes are always concluded to be faster, and most of the time the thinner 40c-ish tire of the gravel bike is ID'd as the biggest contributor. So the mountain bike world is going fatter, the gravel bike world is going fatter - but not too fat because MTB's are slow? Then if you go to the rolling resistance website fat knobby tires with cheaper rubber consistently cost watts. Obviously there are too many factors not being accounted for - namely the actual trail/road, and rider fatigue and confidence, would be the too biggest ones. I have been beating on cyclocross bikes for years, but am looking to switch to a 29'r to take it easy on a botched shoulder. I just want to know how much speed I'll be giving up when I make the switch. ???